“Iron Man 2” is a curious misfire. Given that the original 2008 film pulled the superhero genre out of the cape and cowl doldrums and gave it a rock star status, this one seems less focused, less confident. The other film had a firm narrative, a good story, but this one seems to be put together piecemeal. It has too many characters, not enough of the villian and a third act that ends before it begins. Also, this is an oddly mean-spirited movie. There’s a lot of hostility here that might seem justified, but also seems underdeveloped.

Maybe I am being too harsh. Looking over the superheroes films that have come along since 2008’s Iron Man, it would be hard to compete with the likes of “The Dark Knight” and “Watchmen” so maybe the bar has been set so high there was no way that it could meet that standard.

“Iron Man 2″‘s invaluable asset is, once again Robert Downey, Jr. He knows how to take the role of a billionaire playboy with an endless supply of weapons and toys and turn it into a kind of stand-up routine. His chief asset though is his mouth and we can see that during a virtuoso opening sequence in which he trounces a stuffy Senator (Garry Shandling) who is trying to suggest that his Iron Man suit is a WMD that should be turned over to the military. He makes himself a media sensation by announcing “I have successfully privatized world peace.” He’s such a brilliant showman that we believe a statement like that without a second thought.

Far away, off Stark’s radar is a brooding hulkish man who doesn’t agree. He is Ivan Vanko (Mickey Rourke), a disgruntled Russian physicist who bears deep resentment toward Stark because his late father helped develop the technology that has made Stark’s family into billionaires and died penniless and forgotten. He vows vengeance against his adversary and develops two cool-looking electrified whips which he intends to use to take Stark out. As played by Mickey Rourke, we see him as a ball of anger with a garbled accent, gold teeth and body marred by an overdose of mafia tattoos. Vanko is recruited by Justin Hammer (Sam Rockwell), an opportunist who wants to use the man’s metalurgic genius to steal Stark’s technology.

That’s the main story, the personal story is actually far more interesting. Tony’s relationship with Pepper is tempered by a secret that he won’t reveal to her (and I, in turn, won’t reveal to you). That secret is at the center of their relationship and it is the thing that it tearing it apart. The tension resides not only within that secret but also in the weight of Stark’s personality. How can Pepper, who runs Stark Industries, maintain a relationship with a man who, basically, behaves like a giant parody of himself?

What director John Favreau does with Iron Man 2 is keep up the pace of the original, if not the inventiveness. The movie is a red-blooded action picture all full of neat gizmos and perfect throw away moments. His action scenes are expertly handled, none better than a brilliant sequence on a racetrack in Monaco. Stark commandeers a race car that he owns only to have it sliced in half on the track by Ivan’s electric whips. That sequence makes the movie for me and it is so effective that it casts a pall over the action scenes that follow. They aren’t bad, but somehow I got the feeling that the movie played it’s best hand too early.

Mickey Rourke, who seems to be on the comeback trail after his bravura performance in The Wrestler occupies the role of Ivan Vanko with a cold, muted detatchment. Many of his scenes have him sitting back and speaking through a tar-soaked Russian accent that is often difficult to understand. There’s something underwhelming about his performance, which he seems to play without any kind of fire or passion.

The biggest disappointment is the film’s third act. The showdown between Stark and Vanko seems very brief, almost as if it had been edited. The two adversaries meet and then suddenly its over. There’s no punch or drama to it, it is over much too quickly. The movie establishes a conflict between Tony and his late father and the conflict brewing in Ivan over his dead father but it never brings the two stories together. The third act is a loud, clanking battle but when it comes around to dealing with the personal issue, pulls up short. That doesn’t make the movie bad, but it does leave you a little cold.